At least one contributor to this blog plays hockey (and the image here may be the stick he uses, in fact); it's good to know that he's capable of some form of communication beyond snarky blog posts.

Here's a key piece of the story, from biologists at Stanford:

“We found that hockey players can use stick-banging to indicate anything from disagreement with a referee to encouragement of their teammates,” said lead researcher Dr. Margaret Cundiff, who explained that players typically strike the boards a single time with force when they want to display anger, or use multiple softer taps in order to display approval. “Sometimes, an entire bench full of players will begin banging the boards in unison—either signaling that a goal has occurred, or that the players want a goal to occur. This actually lets hockey players ‘speak’ to each other, if you will, in surprisingly complex ways far beyond what was previously anticipated. They are truly magnificent creatures.”